# trunk/43b3e72193745ae3c6c5394f05bbe6a79b43f641: [CI] Restrict the LF fleet to the allowlisted runner types (#200862)

> **Key Architectural Takeaway:** Impact: CI only Risk: low What Flips lf_allowlist.mode in .github/arc.yaml from all to restricted .

**Published:** 2026-10-14T00:22:51+00:00 
**Source:** PyTorch GitHub Releases 
**Category:** bigtech-foss 
**Canonical URL:** https://fosswire.org/news/trunk43b3e72193745ae3c6c5394f05bbe6a79b43f641-ci-restrict-th.html 

## Executive Summary
Impact: CI only Risk: low What Flips lf_allowlist.mode in .github/arc.yaml from all to restricted . With that, only the runner types in the allowlist can keep the lf- prefix. Any other test-matrix job that would have gone to LF gets rewritten to mt- and runs on the Meta clusters. Why Part of pytorch/ci-infra#1081 . The wiring that enforces the allowlist is already on main. This is the switch that turns it on, so day-to-day LF usage is limited to the 9 ARC targets listed in the file (the x86 avx512/amx CPU shapes, the L4/A10G GPU shapes and the default arm64 build runner) and everything else moves to Meta.

## Architectural & Systems Analysis
From a silicon and hardware engineering viewpoint:

- **Interface Neutrality:** Mitigates dependency on proprietary BSPs, empowering open toolchains to address hardware directly.
- **Supply Chain Verification:** Schematics and open pinouts allow deterministic audits against silicon errata.
- **Lifecycle Decoupling:** Decouples physical hardware utility from commercial vendor end-of-life obsolescence.

## Impact on the Open Ecosystem
Ensures that computational autonomy remains in the hands of the architect rather than closed silicon vendors.